Department of Medicine, New York University School of Medicine, New York, NY.
Division of Rheumatology, Department of Medicine, Johns Hopkins University, Baltimore, MD.
Rheumatology (Oxford). 2022 Nov 2;61(11):4335-4343. doi: 10.1093/rheumatology/keac067.
Delayed detection of LN associates with worse outcomes. There are conflicting recommendations regarding a threshold level of proteinuria at which biopsy will likely yield actionable management. This study addressed the association of urine protein:creatinine ratios (UPCR) with clinical characteristics and investigated the incidence of proliferative and membranous histology in patients with a UPCR between 0.5 and 1.
A total of 275 SLE patients (113 first biopsy, 162 repeat) were enrolled in the multicentre multi-ethnic/racial Accelerating Medicines Partnership across 15 US sites at the time of a clinically indicated renal biopsy. Patients were followed for 1 year.
At biopsy, 54 patients had UPCR <1 and 221 had UPCR ≥1. Independent of UPCR or biopsy number, a majority (92%) of patients had class III, IV, V or mixed histology. Moreover, patients with UPCR <1 and class III, IV, V, or mixed had a median activity index of 4.5 and chronicity index of 3, yet 39% of these patients had an inactive sediment. Neither anti-dsDNA nor low complement distinguished class I or II from III, IV, V or mixed in patients with UPCR <1. Of 29 patients with baseline UPCR <1 and class III, IV, V or mixed, 23 (79%) had a UPCR <0.5 at 1 year.
In this prospective study, three-quarters of patients with UPCR <1 had histology showing class III, IV, V or mixed with accompanying activity and chronicity despite an inactive sediment or normal serologies. These data support renal biopsy at thresholds lower than a UPCR of 1.
LN 的延迟检测与更差的结果相关。对于蛋白尿水平达到何种程度进行活检可能会获得可操作的管理，目前存在相互矛盾的建议。本研究旨在探讨尿蛋白与肌酐比值（UPCR）与临床特征的关系，并调查 UPCR 在 0.5 至 1 之间的患者中增生性和膜性组织学的发生率。
在临床指示性肾活检时，共招募了 275 名 SLE 患者（113 名首次活检，162 名重复），这些患者来自美国 15 个地点的加速药物合作联盟的多中心多民族/种族研究。患者随访 1 年。
在活检时，54 名患者的 UPCR <1，221 名患者的 UPCR ≥1。独立于 UPCR 或活检数量，大多数（92%）患者的组织学为 III、IV、V 或混合性。此外，UPCR <1 且具有 III、IV、V 或混合性的患者的活动指数中位数为 4.5，慢性指数为 3，但 39%的这些患者的尿液沉渣处于不活动状态。在 UPCR <1 的患者中，既没有抗 dsDNA 也没有低补体可以区分 I 类或 II 类与 III、IV、V 或混合性。在基线 UPCR <1 且具有 III、IV、V 或混合性的 29 名患者中，23 名（79%）在 1 年内 UPCR <0.5。
在这项前瞻性研究中，尽管尿液沉渣处于不活动状态或血清学正常，但四分之三的 UPCR <1 的患者的组织学显示出 III、IV、V 或混合性，伴有活动和慢性。这些数据支持在 UPCR 低于 1 的阈值下进行肾活检。
